Expander roll



Patented Jan. 15, 1946 ori-ici:l

EXPANDER Roni.l John D. Robertson, Taunton, Mass. Application February 2,1, 1945, Serial No.`579,'122-" (o1. 26463) 'I 3 Claims.

This invention relates to improvements in expander rolls for flexible sheet materials, and more particularly to such rolls having curved or bowed extent between their ends and whose principal utility is for stretching fabric weft-wise andfor removing wrinkles from fabric webs in the course of the rou' sections to further increase national resistance to rotation ofthe sections.

of their travel to or from any of various textile y machines or frames.

Expander rolls of the general type to which the invention relates ordinarily have a surface of rubber or other resillently flexible material engaged over a, series of roll sections which are rotatably mounted on a curved axially extending shaft held at itsgpposite ends in clamps customf arily mounted on the frame of the particularA machine with which the expander roll is-associated. The web of cloth comes to the roll at the inner side of its bowed extent and leavesy the roll at its outer side, the rubber surface element of the roll having to expand and contract as the roll rotates to accommodate the enclosed roll sections.

desired spreading effect of the roll weftwise of the fabric with the result that relatively little increase in the width of the fabric has beeny at-u Various-*attempts have been made heretofore to reduce friction in curved expander rolls so 'that a rollA as an entirety might Ibe more' sensitive'to draft vof a' web of fabric trained thereover.l The 1 seemingly obviousremedyof mounting the roll sections'on ball bearings was among the things tried fand foundy impractical andi unsuccessfult due' to rapid gumming of the balls which in a short time prevented relative rotation of the ball races. 'JAS soon as this condition occurred in one roll section, any further rotation of the roll as a whole about the shaft involved rotation of'both inner and outer ball races of the stuck unit, which scored-the shaft-and resulted in hastenlng clog ging and sticking of adjacent ball units until the roll ultimately'became entirely unfit "for'servica It is among the objects of the invention to Aprovidean expander roll which can serve efciently; andeifectively for expanding or spreading ex'- ible sheet materials generally including delicate and sheer textile fabricsfzand without imposing 1 on thesheets or ywebs any damaging ,lamount of warpwise tensional strain. I provide an improved curved-.or bowed roll constructionxhavingroll sec-4v e tions which arerelatively freely rotatable on their support shaft, and having a resilientlyfiexible surfaceitube of rubber or the likevwhich more readily and smoothly can execute requisite expansions and contractions as compared with prior rolls, and which in consequence canhave a subtainable with the prior curved expander grolls.

Also; the mentioned warpwise tensional strains` have been so severe as sometimes to damage even the more stable and rugged fabrics. Sheer anddelicate fabrics could not safely be subjectedfto the action of the prior rolls in any event.A Also it stresses acting' f gagement between the adjacent roll sections to insure that no one or more sections wouldbe held `against rotation by accumulations of foreign matter or corrosion at bearing regions. customarily,

.the roll sections have been provided at their ends with coacting clutch teeth or the like whichinvolve substantial amounts of frictional rubbing due to the different planes of rotation of the interlooked roll sections. Also the abrasive action at 's'tantially-prolonged*useful life because of reduced abrasiveaction ofthe cloth on the rubber surface. Anotherobject `is to provide an expander roll structure. comprising a series vof spacedroll sections each rotatable on a; separate anti-friction Y bearing `unit and allfof the ysections rotatably supported on'a Vcurved supporting shaftrand covy eredbyy airesilentlynexible surface tube of rubay bero'r the like. v A further object is to provide an expander roll `having aseries of. ro`ll sections'r rotatablyspaced apart .on a nonlround longitudinally curved frigid supporting shaft'. l Still'another object 'is to/provide 'a longtudinally curvedv expander rollhavrig a ysupporting shaft with straight end sectionsjgenerally tanjfv gent to the adjacent curved portions, and anni-Q versally adjustable clamp securing the randstad-Q tions of shaft with the curved extentof the shaft" in any pf various'planes.

the clutch teeth causedsubstantial quantities of 1 abraded particles to get into the bearing bushings l Yet* another `object is'to provide allongitudig' nally vpuri/ed expander roll fand end' `-clamps for thejopposite'ends of the roll,' each clamp having'.

universally adjustable jaws for receiving'an end of Vsaid4` roll disposed'v in any of a variety'. 0,f anj @guiar-pfositionsry sion of elements is attained between the retaining rings ,56, with all of the inner races B and the spacing sleeves 68 stationary on shaft I0.

In the detail showing of Fig. 2, it will be seen that the roll sections 36, 38 each has an interior annular shoulder 'lll for seating the end of the casing 64 of a ball bearing unit. Also, in Fig. 2, the inner race of the ball bearing unit within the endmost roll section 3B is shown engaged against the retaining ring 56. The next adjacent ball bearing unit, in the roll section 3B, is held spaced from the endmost urn't by one of the cylindrical spacing sleeves 68 which is loose on shaft i0. Similarly, the ball bearing units in all other roll sections 38 are spaced apart throughout the extent of the roll by spacing sleeves 68 engaged one between adjacent inner ball races Ell.

Preferably, the interior shoulders lil of roll sections 36, 38 on one side of the mid-point along the roll will face in one direction and on the other` side of saidr mid-point will face in the opposite direction.

The generally curved contour of my improved composite roll involves rotation of the individual roll sections 3S, 38 in planes which are slightly inclined with respect to each other. This is permissible with my disclosed structure due to the spacing apart of the roll sections as at l2. The opposite ends of each roll section are in parallel planes with the result that the space 12 between roll sections is wider at the convex side of the bow than on the concave side, which permits contraction of the rubber surfacing tube 5D on said concave side and causes stretching or expansion of the tube at said convex side of the bow, with the tube 40 bridging the spaces between roll sections to provide a continuous traction surface from one end to the other of the roll.

In use, a web of fabric or the like F comes to the roll at the concave side of its bowed extent at which side the length of the roll surface is materially less than at the convex side. The web is trained around the roll more or less, depending upon the degree of expansion of the web which is desired. Fig. 1 illustrates a web F having approximately a 180 engagement with the roll which provides a maximum of web expanding effect with the particular roll curvature as illustrated.

An important feature of the invention is the provision of an expander roll which is efcient and practical for handling all kinds of fabric webs including the sheer and delicate fabrics which heretofore could not safely be subjected to the action of prior curved expander rolls. My improved roll structure places a minimum of tensional strain warpwise on a fabric which is being expanded or spread laterally, and the resiliently iiexible tubular roll surface more gently and easily executes its expansions and contractions under the influence of the roll sections, thereby increasing substantially the useful life of the surface tube as compared with prior rolls because of the reduced amount of abrasive action of the cloth on the rubber.

Also my improved end clamps co-act in reducing destructive strains on the clamps and on the roll to a minimum, while providing greater security of clamping and a superior degree of adjustability for setting the roll with its bowed extent in any selected plane. Also, my roll shaft may have its straight end portions I2 generally tangent to the adjacent curved portions which is important in that the inner ball races 60 and the spacing sleeves 68 readily may be slipped over the straight end portions of the shaft and moved to their proper positions along the curved portions thereof.

I claim as my invention:

`1. An expander roll for exible sheet material, comprising a rigid longitudinally curved shaft having an angular cross-section, a series of antifriction bearing units distributed in spaced relation along the shaft, each said unit including an inner part having an axial angular hole in which the shaft engages non-rotatably and an outer part which is freely rotatable on the inner part, a rigid tubular sleeve loose on the shaft between adjacent bearing units and maintaining the said spaced relation of the units, a series of cylindrical roll sections each mounted on a said outer part of a bearing unit for rotation therewith, at least some of said roll sections being canted slightly with respect to next adjacent roll sections, an end cap secured to each endmost roll section and having an axial hole for loose passage of said shaft, a retaining ring fixed on the shaft between the end wall of a said cap and the adjacent endmost bearing unit for maintaining said unit against outward longitudinal movement along the shaft, and a resiliently flexible tubular surface member covering all of the roll units and having its ends butted against said end caps.

2. An expander roll for flexible sheet material, comprising a longitudinally curved shaft having an angular cross-section throughout and having straight end portions, multiple roll sections rotatable on the curved portion of the shaft, a flexible tube covering all of the roll sections and bridging spaces between the roll sections, intertting means having interioll angularly related surfaces loosely engaging angularly related surfaces of a said straight end portion of the shaft whereby the inter-fitting means and the shaft are maintained against relative rotation, said intertting means having exterior generally spherical surfaces, a support having an interior generally spherical recess of xed dimensions within which said inter-fitting means and the looselyengaged shaft are adjustable as a unit around the axis of the end portion of the shaft, and means for securing the inter-fitting means in selected adjusted positions within said recess of the support.

3. An expander roll for flexible sheet material, comprising a longitudinally curved shaft having an angular cross-section throughout and having straight end portions, multiple roll sections rotatable on the curved portion of the shaft, a flexible tube covering al1 of the roll sections and bridging spaces between the roll sections, interiitting means having interior angularly related surfaces loosely engaging angularly related surfaces of a said straight end portion of the shaft whereby the inter-fitting means and the shaft are maintained against relative rotation, said inter-fitting means having exterior generally spherical surfaces, a support having an interior generally spherical recess of fixed dimensions within which said inter-fitting means and the loosely engaged shaft are adjustable as a unit around the axis of the end portion of the shaft, and means for clamping the inter-fitting means on the end portion of the shaft and for simultaneously securing the inter-fitting means in a selected adjusted position within said fixed dimen- 

